However, Valve failed to confirm the speculation and following the disappearing act first noticed by the Valvetime fan site, it now appears as if the post may have been a fabrication.

As other sources reported last week, the application filed with the European Office for Harmonisation in the Internal Market was not replicated in the US Patents and Trademarks Office - a further sign it was a hoax.

Demand

The removal of the application, which listed Valve as the owner of the property, is unlikely to quell speculation that another sequel could or should be on the way.

It may actually see demand for a new game reach such levels that Valve will struggle to get away with not making one.